The LuxS family of bacterial autoinducers: biosynthesis of a novel quorum-sensing signal molecule.

TitleThe LuxS family of bacterial autoinducers: biosynthesis of a novel quorum-sensing signal molecule.
Publication TypeJournal Article
Year of Publication2001
AuthorsSchauder, S, Shokat, K, Surette, MG, Bassler, BL
JournalMol Microbiol
Volume41
Issue2
Pagination463-76
Date Published2001 Jul
ISSN0950-382X
Keywords4-Butyrolactone, Bacterial Proteins, Carbon-Sulfur Lyases, Cell Extracts, Cell-Free System, Dialysis, Genomics, Homocysteine, Homoserine, Lactones, Luminescent Measurements, Mass Spectrometry, Multigene Family, S-Adenosylmethionine, Salmonella typhimurium, Signal Transduction, Vibrio
Abstract

<p>Many bacteria control gene expression in response to cell population density, and this phenomenon is called quorum sensing. In Gram-negative bacteria, quorum sensing typically involves the production, release and detection of acylated homoserine lactone signalling molecules called autoinducers. Vibrio harveyi, a Gram-negative bioluminescent marine bacterium, regulates light production in response to two distinct autoinducers (AI-1 and AI-2). AI-1 is a homoserine lactone. The structure of AI-2 is not known. We have suggested previously that V. harveyi uses AI-1 for intraspecies communication and AI-2 for interspecies communication. Consistent with this idea, we have shown that many species of Gram-negative and Gram-positive bacteria produce AI-2 and, in every case, production of AI-2 is dependent on the function encoded by the luxS gene. We show here that LuxS is the AI-2 synthase and that AI-2 is produced from S-adenosylmethionine in three enzymatic steps. The substrate for LuxS is S-ribosylhomocysteine, which is cleaved to form two products, one of which is homocysteine, and the other is AI-2. In this report, we also provide evidence that the biosynthetic pathway and biochemical intermediates in AI-2 biosynthesis are identical in Escherichia coli, Salmonella typhimurium, V. harveyi, Vibrio cholerae and Enterococcus faecalis. This result suggests that, unlike quorum sensing via the family of related homoserine lactone autoinducers, AI-2 is a unique, 'universal' signal that could be used by a variety of bacteria for communication among and between species.</p>

DOI10.1046/j.1365-2958.2001.02532.x
Alternate JournalMol. Microbiol.
PubMed ID11489131